Acoustic devices are widely used in modern electronics. Exemplary acoustic devices include surface acoustic wave (SAW) filters and bulk acoustic wave (BAW) filters, which are increasingly used in the transmission and reception of radio frequency (RF) signals for wireless communications.
Current and emerging applications, such as Base Station Small Cells, pre-5G, 5G, massive multiple-inputs/multiple outputs (MIMO), Repeaters, and Boosters, often require higher levels of RF/acoustic power handling by the acoustic devices. For the acoustic filter, the increased heat generation during its operation may greatly affect the frequency stability of filter response and impede the desired performance of the acoustic filters. Due to device architecture as well as component packaging requirements of the acoustic device, it is typically not efficient to provide a thermally conductive path from the top-side of the acoustic device. In such situations, a superior thermal dissipation path that removes the heat away from the back-side of the acoustic device is desired.
Typically, an acoustic device leverages epoxy based materials for attaching a conventional acoustic die to a substrate. Due to the relatively low thermal conductivity of die-attach epoxies, the thermal impedance of the heat removal path at the back-side of the acoustic device is relatively high. To accommodate the increased heat generation within the acoustic devices, it is therefore an object of the present disclosure to provide an improved design for high-power acoustic devices. Further, there is also a need to improve the performance of the acoustic device without significantly increasing the device size.